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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Biodiversity potential in the Pacific and Inland Northwest the relative importance of forest structure and available energy in driving species diversity /

Verschuyl, Jacob Pieter January 2007 (has links) (PDF)
Thesis (Ph. D.)--Montana State University--Bozeman, 2007. / Typescript. Chairperson, Graduate Committee: Andrew J. Hansen. Includes bibliographical references.
42

Choosing efficient land allocations and forest management regimes for biodiversity /

Shunk, Neal J. January 2000 (has links)
Thesis (M.S.)--Oregon State University, 2001. / Typescript (photocopy). Includes bibliographical references (leaves 50-53). Also available on the World Wide Web.
43

Granivores as ecosystem regulators of woody plant increasers in semi-arid Savannas of the Lowveld, South Africa

Petersen, Leif Michael January 2006 (has links)
Magister Scientiae - MSc (Biodiversity and Conservation Biology) / In recent years, a global trend of increasing woody vegetation densities in semi-arid savanna habitats has been recorded, commonly described in South Africa as 'bush encroachment'. The shrubs and trees that do this (Increasers) have wrought significant economic and ecological impacts upon carrying capacities of large areas of savannas. This occurs, as suitable grazing areas are incrementally engulfed in shrubs and trees establishing new equilibria, from open savannas (essentially grasslands with scattered trees) into closed woodlands (treelands with scattered grasses). This thesis demonstrated a link between grass biomass, small mammal abundance and diversity, and their potential increaser seed/seedling predatory activities in the semi-arid Lowveld Savannas of South Africa. / South Africa
44

Conservation of terrestrial biodiversity in Hong Kong /

Chu, Wing-hing. January 1998 (has links)
Thesis (M. Phil.)--University of Hong Kong, 1998. / Includes bibliographical references (leaves 129-138).
45

Validity of biodiversity monitoring programmes : Boundary Stream Mainland Island Project, Department of Conservation : a thesis submitted to Canterbury University in part fulfilment of the requirements of the degree of Master of Forestry Science, University of Canterbury /

Christensen, Brendon Rex. January 2003 (has links)
Thesis (M. For. Sc.)--University of Canterbury, 2003. / Typescript (photocopy). Includes bibliographical references (leaves 112-137). Also available via the World Wide Web.
46

Granivores as ecosystem regulators of woody plant increasers in semi-arid Savannas of the Lowveld, South Africa.

Petersen, Leif Michael. January 2006 (has links)
<p>In recent years, a global trend of increasing woody vegetation densities in semi-arid savanna habitats has been recorded, commonly described in South Africa as 'bush encroachment'. The shrubs and trees that do this (Increasers) have wrought significant economic and ecological impacts upon carrying capacities of large areas of savannas. This occurs, as suitable grazing areas are incrementally engulfed in shrubs and trees establishing new equilibria, from open savannas (essentially grasslands with scattered trees) into closed woodlands (treelands with scattered grasses). This thesis demonstrated a link between grass biomass, small mammal abundance and diversity, and their potential increaser seed/seedling predatory activities in the semi-arid Lowveld Savannas of South Africa.</p>
47

An analysis of landscape diversity on the floodplain of a Scottish wandering gravel-bed river

Parsons, Helena January 2000 (has links)
This thesis examines landscape diversity within alluvial valley floors using the case study of a Scottish wandering gravel-bed river. The thesis aims are two-fold; firstly to investigate the spatial and temporal patterns of valley floor landscape diversity within semi-natural environments, and secondly to develop a methodology for quantifying alluvial valley floor landscape diversity in space and time. The diversity analysis involves quantifying the spatial patterns of geo-, pedo- and biodiversity (flora) within floodplain zones which have been exposed to approximately 100 years of recovery since flood embankment abandonment along the most active reaches of the river. In addition historical records including aerial photographs, maps and narrative accounts were used to assess the temporal patterns of the diversity of landscape patches and how they have changed through time using a series of landscape indices. The analysis thus accounts for the role of river channel change in producing a complex mosaic of land cover types within alluvial valley floors. The spatial analysis revealed that landscape diversity tends to be greater in the perpendicular orientation to the main channel, i.e. along an aquatic-to-terrestrial environmental gradient. The temporal analysis results revealed that the landscape over the last 50 years has changed from being dominated by few relatively large isodiametric patches to a landscape dominated by small irregular shaped patches. Thus although landscape patch richness has increased along with an increase in land cover types through time, the landscape patches have also become more fragmented. The major outcomes of the research are the deriving of quantitative results of the spatial and temporal patterns of floodplain landscape diversity, an evaluation of the role of channel dynamics in creating the diverse mosaic of land cover types, the identification of the environmental controls and supporting floodplain habitats of a number of rare species and a proposed methodology for assessing landscape diversity to be validated on other river systems.
48

The contribution of Multi-tenure reserve networks to biodiversity conservation.

Fitzsimons, James Andrew, mikewood@deakin.edu.au January 2004 (has links)
A consistent and integrated approach to nature conservation across the landscape and regardless of tenure is widely recognised as essential in ensuring the effective conservation of biodiversity. 'Multi-tenure reserve networks', which incorporate public and private lands managed for conservation, are considered a means of achieving landscape scale conservation. Biosphere Reserves (BR) and Conservation Management Networks (CMN) are characteristic models in Australia. This thesis aims to evaluate the role of such networks in protecting biodiversity, specifically by: (1) analysing the spatial configuration (size, shape, connectivity) of networks and their individual components; (2) evaluating the contribution of networks (in real terms and in reporting procedures) to biodiversity conservation objectives; (3) analysing the influence of the attitudes and perceptions of land managers on the functionality of networks; and (4) evaluating the influence of coordinating bodies on network functionality. In order to account for deficiencies in existing classifications of conservation lands, a new classification system was developed for this thesis - the Conservation Lands Classification. This classification incorporates conservation mechanisms on public and private lands and forms the basis for comparing network components in three Australian case studies - the Bookmark BR located in the Murray Mallee of South Australia, the Gippsland Plains CMN on the eastern Gippsland Plains of Victoria and the Grassy Box Woodlands CMN across the inland slopes of New South Wales. The spatial configuration of individual components within networks was measured using spatial analysis techniques within a geographic information system (GIS). GIS was also used to measure the contribution that networks made to a comprehensive, adequate and representative reserve system through the ecosystems they protected. The attitudes and perceptions of landowners and managers within the networks were obtained using questionnaires. Questionnaires were also sent to network coordinators. Statistical and descriptive analysis was conducted on the results. The sizes of individual components varied markedly between the three networks, however within each network public reserves were on average larger than private conservation lands. Although levels of physical connectivity varied between networks, Bookmark BR and Gippsland Plains CMN showed greater similarity to each other than to the Grassy Box Woodlands CMN. The findings raise important questions about the real and perceived differences in the BR and CMN models. All networks, and particularly those components outside the public protected area estate, contributed to enhancing the protection of ecosystems unrepresented or under-represented in the reserve system, although the extent of this contribution varied between networks. Trade-offs between reserve design efficiency and a contribution to a comprehensive, adequate and representative reserve system were evident between networks. Bookmark BR was characterised by high connectivity, strong reserve design integrity but a lower contribution to protecting under-reserved ecosystems, whereas the opposite was evident in the Grassy Box Woodlands CMN. Over 88% of managers considered their involvement in multi-tenure reserve networks to be a positive or very positive experience. A lack of resources and time for management were considered major limitations of these networks. The majority (80%) of private land managers within networks were willing to be included in a national reserve system of conservation lands. This has important implications for the Australian National Reserve System, which currently incorporates mostly public land. The changing nature of the network coordination arrangements suggests an organic fluid evolution of network structures is likely, contrasting with the desire for legalistic and administrative rigidity promoted by government agencies. The thesis concludes that all the networks studied contribute in varying degrees to biodiversity conservation. The key factors influencing the current and potential contribution that such networks make are: (1) the aims, directions and restrictions set by or imposed upon the coordinating body; and (2) the biophysical nature of the surrounding bioregion and resultant historical land use and tenure pattern. Although the successful operation of such 'multi-tenure' networks ultimately relies on the willing participation of private landholders, ongoing institutional support is likely to be required for maintaining networks in the longer term. Considering networks are increasingly formed outside of the influence of government institutions, this presents a significant challenge for effective coordinated conservation.
49

Levande fäbodbruk på 2000-talet : -svårigheter respektive möjligheter

Rönnow, Anna January 2010 (has links)
Mountain holding in the 21st century – difficulties and possibilities   This study examines the difficulties and possibilities that mountain holding farmers have today. The following questions were considered: i) Who is cultivating mountain holdings today? ii) Which is the most important reason to keep animals there? iii) What kind of subsidies are most common? iv) What kinds of animals and what breeds are the most common? v) For how long period of time are the animals kept at the mountain holdings every season? vi) How are the fundamental regulations in the animal welfare law being followed, and are there any problems/conflicts in keeping animals at the mountain holdings? vii) What meaning do the animals have for the farmers and what are the farmer’s thoughts about the future? A survey based on these issues was sent out to 107 mountain holdings farmers with animals on grazing land, where 59 % submitted a response. The results showed that knowledge on how to keep animals at the mountain holdings was overall good. The biggest difficulties for the farmers were not following the current regulations but an increased number of predators and poor profitability. 45 % of 62 responders thought predators were a problem and 35 % that poor profitability was a problem. The possibilities that farmers have are mostly to focus their resources on tourism. Today we talk about biological diversity, locally produced and national particularities, and from this study I think that the mountain holdings have several important functions to fill there.
50

Development and management framework for the Gouritz River Catchment

Griesel, Gerhard. January 2003 (has links)
Thesis (M.L. Arch.)--University of Pretoria, 2003. / Includes bibliographical references.

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